The identification and selection of a solid form of a pharmaceutical compound are complex, given that a change in solid form may affect a variety of physical and chemical properties, which may provide benefits or drawbacks in processing, formulation, stability, bioavailability, storage, handling (e.g., shipping), among other important pharmaceutical characteristics. Useful pharmaceutical solids include crystalline solids and amorphous solids, depending on the product and its mode of administration. Amorphous solids are characterized by a lack of long-range structural order, whereas crystalline solids are characterized by structural periodicity. The desired class of pharmaceutical solid depends upon the specific application; amorphous solids are sometimes selected on the basis of, e.g., an enhanced dissolution profile, while crystalline solids may be desirable for properties such as, e.g., physical or chemical stability (see, e.g., S. R. Vippagunta et al., Adv. Drug. Deliv. Rev., (2001) 48:3-26; L. Yu, Adv. Drug. Deliv. Rev., (2001) 48:27-42).
Whether crystalline or amorphous, solid forms of a pharmaceutical compound include single-component and multiple-component solids. Single-component solids consist essentially of the pharmaceutical compound or active ingredient in the absence of other compounds. Variety among single-component crystalline materials may potentially arise from the phenomenon of polymorphism, wherein multiple three-dimensional arrangements exist for a particular pharmaceutical compound (see, e.g., S. R. Byrn et al., Solid State Chemistry of Drugs, (1999) SSCI, West Lafayette). The importance of discovering polymorphs was underscored by the case of Ritonavir™, an HIV protease inhibitor that was formulated as soft gelatin capsules. About two years after the product was launched, the unanticipated precipitation of a new, less soluble polymorph in the formulation necessitated the withdrawal of the product from the market until a more consistent formulation could be developed (see S. R. Chemburkar et al., Org. Process Res. Dev., (2000) 4:413-417).
Notably, it is not possible to predict a priori if crystalline forms of a compound even exist, let alone how to successfully prepare them (see, e.g., Braga and Grepioni, 2005, “Making crystals from crystals: a green route to crystal engineering and polymorphism,” Chem. Commun.: 3635-3645 (with respect to crystal engineering, if instructions are not very precise and/or if other external factors affect the process, the result can be unpredictable); Jones et al., 2006, Pharmaceutical Cocrystals: An Emerging Approach to Physical Property Enhancement,” MRS Bulletin 31:875-879 (At present it is not generally possible to computationally predict the number of observable polymorphs of even the simplest molecules); Price, 2004, “The computational prediction of pharmaceutical crystal structures and polymorphism,” Advanced Drug Delivery Reviews 56:301-319 (“Price”); and Bernstein, 2004, “Crystal Structure Prediction and Polymorphism,” ACA Transactions 39:14-23 (a great deal still needs to be learned and done before one can state with any degree of confidence the ability to predict a crystal structure, much less polymorphic forms)).
The compound chemically named 2-(tert-butylamino)-4-((1R,3R,4R)-3-hydroxy-4-methylcyclohexylamino)-pyrimidine-5-carboxamide (alternatively named 2-[(1,1-dimethylethyl)amino]-4-[[(1R,3R,4R)-3-hydroxy-4-methylcyclohexyl]amino]-5-pyrimidinecarboxamide) and tautomers thereof (collectively referred to herein as “Compound 1”) are disclosed in U.S. Patent Application Publication No. 2013/0029987, published on Jan. 31, 2013, and International Pub. No. WO2012/145569, the entireties of each of which are incorporated by reference herein.
The variety of possible solid forms creates potential diversity in physical and chemical properties for a given pharmaceutical compound. The discovery and selection of solid forms are of great importance in the development of an effective, stable and marketable pharmaceutical product.
The connection between abnormal protein phosphorylation and the cause or consequence of diseases has been known for over 20 years. Accordingly, protein kinases have become a very important group of drug targets. (See Cohen, Nature, 1:309-315 (2002), Gaestel et al. Curr. Med. Chem. 14: 2214-223 (2007); Grimminger et al. Nat. Rev. Drug Disc. 9(12):956-970 (2010)). Various protein kinase inhibitors have been used clinically in the treatment of a wide variety of diseases, such as cancer and chronic inflammatory diseases, including rheumatoid arthritis and psoriasis. (See Cohen, Eur. J. Biochem., 268:5001-5010 (2001); Protein Kinase Inhibitors for the Treatment of Disease: The Promise and the Problems, Handbook of Experimental Pharmacology, Springer Berlin Heidelberg, 167 (2005)).
JNK is a ubiquitously expressed serine/threonine kinase belonging, together with ERK (extracellular-regulated kinase) and p38, to the family of mitogen-activated protein kinases (MAPKs). (Kyriakis J M, Sci. STKE (48):pe1 (2000); Whitmarsh A J, et al. Sci. STKE (1):pe1 (1999); Schramek H, News Physiol. Sci. 17:62-7 (2002); Ichijo H, Oncogene 18(45):6087-93 (1999)). MAPKs are important mediators of signal transduction from the cell surface to the nucleus, using phosphorylation cascades to generate a coordinated response by a cell to an external stimulus by phosphorylation of selected intracellular proteins, including transcription factors. Additionally, JNK also phosphorylates non-nuclear proteins, for example, IRS-1, and Bcl-2 family members. (Davis R J, Trends Biochem. Sci. 9(11):470-473 (1994); Seger R et al., FASEB J.; 9(9):726-35 (1995); Fanger G R et al., Curr. Opin. Genet. Dev.; 7(1):67-74 (1997)).
The elucidation of the intricacy of protein kinase pathways and the complexity of the relationship and interaction among and between the various protein kinases and kinase pathways highlights the importance of developing pharmaceutical agents capable of acting as protein kinase modulators, regulators or inhibitors that have beneficial activity on multiple kinases or multiple kinase pathways. Accordingly, there remains a need for new kinase modulators, for example, JNK modulators, and in particular solid forms of those kinase modulators.
Citation or identification of any reference in Section 2 of this application is not to be construed as an admission that the reference is prior art to the present application.